Printing apparatus with hydraulic control



Feb. 18, 1958 w. RITZERFELD ET AL 2,

PRINTING APPARATUS WITH HYDRAULIC CONTROL 4 Sheets-Sheet 1 Filed Nev. 20, 1956 1958 w. RITZERFELD ETl'AL 2,823,604

PRINTING APPARATUS WITH HYDRAULIC CONTROL Filed Nov. 20, 1956 4 Sheets-Sheet 2 Inventory Feb. 18, 1958 w. RITZERFELD ET-AL 2,823,604

PRINTING APPARATUS WITH HYDRAULIC CONTROL Filed NOV. 20, 1956 4 Sheets-Sheet 3 WWW M W F I8, 195 w. RITZERFELD EIAL 2,323,604

PRINTING APPARATUS WITH HYDRAULIC CONTROL Filed Nov. 20, 1956 4 Sheets-Sheet 4 Inventor? United States Patent PRINTING APPARATUS WITH HYDRAULIC CONTROL Wilhelm Ritzerfeid, Berlin-Dahlem, and Gerhard Ritzerfeld, Berlin-Grunewald, Germany Application November 20, 1956, Serial No. 623,384 Claims priority, application GermanyNovember'ZZ, 1955 9 Claims. (Cl. 101-91) The present invention refers to printing apparatus and more particularly to an apparatus for printing individual lines or sections from a printing form on sheets, cards or the like, and more specifically to that type of apparatus which is intended to selectively print any de sired combination of lines or sections of the printing form.

The present invention is particularly applicable to rotary duplicator machines in which a moistened copy sheet is pressed against a master sheet held on a printing roll.

It is a main object of the present invention to provide an apparatus in which the pressure between the printing roll and a counter roll is produced by hydraulic means.

It is another object of the present invention to provide a printing apparatus ,in which the hydraulic means cornprise a device for creating fluid pressure for producing the printing pressure, and control means for controlling the flow of the fluid.

It is another object of the invention to provide a printing apparatus with hydraulic control of the pressure means for the printing operation in which its action is selectively controlled in accordance with the lines or sections of the printing form that are to be reproduced in the printing operation.

it is still another object of the invention to provide an apparatus in which the pressure exerted by the pressure devices is adjustable so as to be regulated in conformity with conditions prevailing in a particular printing job.

With the above objects in view, an embodiment of the invention includes a rotary printing roll mounted on a frame and adapted to have a printing form attached thereto, and a counter roll mounted on said frame, one of the two rolls being movable by hydraulic means for pressing a copy sheet passing between the two rolls against the printing form.

A preferred embodiment of the invention includes a rotary printing roll mounted on a frame and adapted to have a printing form attached thereto, a movable counter roll for pressing a copy sheet passing between the two rolls against the printing form, and hydraulic operating means connected to the counter roll for moving it into printing position and control devices to operate the hydraulic device in accordance to the selection of sections of the printing form.

Another embodiment of the invention in addition includes electromagnetic means for controlling the hydraulic device for operating the counter roll and selector means respectively associated with sections of the printing form for predetermining the action of the hydraulic device.

Another embodiment of the present invention includes actuator means respectively associated with consecutive sections of the printing form and selectively movable into an operative position for mechanically controlling the action of the hydraulic device.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, to-

ice

gether with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 is a lateral, partly diagrammatical elevation of an apparatus according to the present invention, one side wall of the frame being omitted for the sake of clarity and for showing the internal mechanism thereof;

Fig. 2 is a partly sectional plan view of the apparatus shown in Fig. 1, the section being taken along line A-B of Fig. 1;

Fig. 3 is a lateral, partly diagrammatical elevation of another embodiment of the invention, the one wall of the frame being omitted for the sake of clarity; and

Fig. 4 is mainly a'wiring diagram intended to show the electrical means forming part of the embodiment shown in Fig. 3.

Referring now to Figs. 1 and 2, a printing roll 1 is mounted for rotation in the frame vA on a shaft 3, and a printing form 2 comprising sections Z1, Z2, Z3, etc. isattached to the printing roll 1. The printing roll 1 is driven by a motor, .not shown, through a belt 7 and a pulley 6 on an intermediate shaft and by gears 4 and 5 for transmitting the drive from the intermediate shaft to the shaft 3 of the printing roll. The copy sheet 8 is fed by feed rollers 9 and 10 to the printing area indicated by the line CD. A counter roll 12 is supported by arms 11 which turn around a stationary axle 13 and thereby move the counter roll 12 toward the printing roll 1 in order to exert pressure on the copy sheet 8 fed between the counter roll 12 and the form 2 attached to the printing roll 1.

The movement of the counter roll 12 is achieved by operating a set of toggle levers 14 and 15 connected with each other by a pivot pin 16. The toggle lever 15 is turnable around a stationary shaft 22 and abuts in the inoperative position .of the counter roll 12, as shown in Fig. 1, against a stop pin 25. Whenever the toggle lever 15 is turned in clockwise direction as seen in Fig. l, the counter roll 12 is advanced into its printing position.

In this embodiment the movement of the toggle lever 15 and thereby the movement of the counter roll 12 is achieved by hydraulic means.

The hydraulic device shown in Fig. 1 comprises a gear pump 18 which moves hydraulic fluid from the tank 17 toward a cylinder 20a in which a piston 20 is arranged for lengthwise movement. The piston 20 is connected by a link 21 to the outer end of toggle lever 15. Therefore, any movement of the piston 20 is transmitted to the toggle lever 15.

Both ends of the cylinder 20a are connected through ducts 1% and 1912, respectively, to the gear pump 18. A control valve 19 is interposed between the gear pump 18 and the ducts 19a and 19b. The valve 19 is a threeway valve and is controlled from the outside by a lever 41. In the position shown in Fig. 1 .the valve is in a position in which the hydraulic fluid is moved from the gear pump 18 through duct 19b to the lower side of the piston 20 so that in this case the toggle lever 15 is moved to and held in the position shown in Fig. 1 which corresponds to the inoperative position of the counter roll 12. If, however, the control valve 19 is'moved .into its alternative position then .the hydraulic fluid is diverted into the duct 19a which causes the piston to move in a direction opposite to arrow G whereby the toggle lever 15 is moved in clockwise direction as seen in the drawing and the toggle device 14, 15 advances the counter roll 12 into its printing position.

The control valve 19 is operated by a link 40 attached with one end to the lever 41 .and with its other end to a rocker arm '36. This rocker arm 36 swings around a stationary support or pivot 39. The opposite end of the rocker arm 36 is formed as a cam member and operates as will be described later. The movement of the rocker arm 36 is limited in one direction by a stop pin 45 and in the other direction by means described below. A spring 42 tends to return the rocker arm after each operation into the position shown in Fig. 1.

For selectively controlling the operation of the hydraulic device, an actuating device is provided which includes a rotary supporting element 33 mounted for rotation on a secondary shaft 34 and connected by a chain 32 and sprocket wheels30 and 31, respectively, on shafts 3 and 34 to the printing roll 1. The two sprocket wheels 30 and 31 being of the same diameter the rotary element 33 will be rotated in synchronism with the printing roll 1.

Along the circumference of the element 33 and more specifically along a circle concentric to shaft 34, a set of pins S1, S2, S3, etc. is arranged. Each of these pins is associated with one of the sections Z1, Z2, Z3, etc. of the printing form 2. The pins S1, etc. are each movable from an inoperative position into an operative position transversely to the element 33 and are locked in either position by a ball 38 supported by a spring 37 and engaging a corresponding groove in the shank of the pin in either position thereof. The outer end of each pin S1, etc. is provided with a button indexed according to the serial number of the particular pin as for instance S1, S2, etc. and serves for moving manually the selected pin into its operative position shown in Fig. 2. During the rotation of the element 33 the inner projecting ends of the individual pins S1, etc. travel on a circular path concentric to shaft 34. The arrangement is such that the above-mentioned cam member at the end of the rocker arm 36 projects into the circular path of the inner ends of the pins S1, etc. when in operative position. There fore if any one of the pins S1, etc., has been moved into its operative position and the apparatus is started for operation, the pin in operative position will engage or strike the cam member at the end of rocker arm 36 and move the latter in counterclockwise direction as seen in Fig. l. Thereby the control lever 41 of the control valve 19 is moved from position E to position F. Now the fluid is diverted through duct 19a to the upper side of the piston 20 and, as stated before, the movement of the piston forces the counter roll 12 through the toggle linkage into its printing position. The moment the engaging pin S1 etc. has passed the cam end of rocker arm 36, the latter is pulled back into its previous position and the control valve 19 returned to its inoperative position as shown in Fig. 1 in full lines. Thereby the pressure fluid is diverted into duct 19b and forces the piston 20 in the direction of arrow G so that the pressure roller 12 is momentarily returned into its inoperative position.

In order to prevent damage to the apparatus the hydraulic device is provided with two relief valves 23, 24 which are respectively associated with the ducts 19a and 1%. Each valve is provided with a return spring 26 and 27 respectively. While the relief valve 23 has only the function of eliminating excessive pressure and to return the surplus fluid through appropriate channels to the tank 17, the other relief valve 24 associated with duct 19a serves besides a different purpose. It not only causes the return of surplus fluid through a corresponding duct to the tank 17 but also is used for controlling the pressure exerted by the counter roll 12 on the sheet 8. For this purpose this relief valve 24 is adjustable by means of a movable backing 29a for the spring 27. By moving this backing 29a the presetting of the tension in spring 27 can be adjusted. For moving the member 29a a lever 29 is provided which can be swung around a stationary support in either direction and is held in a selected position by a projection engaging notches in an arcuate strip 28. By presetting the tension in spring 27 the pressure can be predetermined at which the valve 24 will open and which is therefore the maximum pressure than can be. exer e 4 on the other side of piston 20 during or at the end of its operative stroke in direction opposite to arrow G.

Sometimes it may be desirable not to select certain sections of the form 2 for reproduction but to reproduce the Whole content of form 2. In that case it is not desirable to have the actuating pins S1, etc. engage the rocker arm 36. As a matter of fact it may be even desirable to leave the pins S1 etc. in an operative position for which they had been set and yet to proceed with a printing operation in which disregarding the setting of the actuating pins a complete reproduction of the entire content of form 2 is obtained. For this purpose a cam control is provided in connection with rocker arm 36. A cam member 43 turnable around a stationary pivot 43a and controlled by an arm 44 is arranged in close proximity with one portion'of rocker arm 36 so that through the action of spring 42 the rocker arm 36 will engage this cam member. In the position shown in Fig. 1 the rocker arm 36 abuts against the cam member 43 and is in a position ready for engagement of its cam end with pins S1. However if the cam control lever 44 is swung in clockwise direction as seen in the drawing until it hits the stop pin 45 then the high portion of the associated cam engages the rocker 36 and moves it in counterclockwise direction so that its cam end is removed from the path of any one of the actuating pins S1, S2, etc.

For clearing the apparatus for a new setting of the actuating pins S1, etc. without individual manual opera tion thereof, a clearing device is arranged close to the rotating element 33. This clearing device includes a lever 46 that can be moved into an operative and an inoperative position. These two positions are defined by stop pins 47 and 49, respectively, a spring tends to hold the lever 46 in either position. Whenever the lever 46 by some outside control is moved into its operative position shown in dotted lines in Fig. 1, then its outer end projects into the path of the pins S1, etc. in operative position. Thereby during a rotation of the element 33 all pins S1 etc. that had been in operative position engage the end of lever 46 and are thereby pushed back into inoperative position.

Referring now to the embodiment shown by Figs. 3 and 4, the general arrangement regarding the printing roll 1 and its drive means, and also the general structure of the hydraulic and mechanical means for moving the counter roll 12 into and out of printing position are the same as in the previous embodiment.

However, the operation of the control valve 19 is done not mechanically but by electromagnetic means. A solenoid 55 is mounted in the frame A and its armature is connected by a link 56 with the control arm 41 of control valve 19. Whenever the solenoid 55 is energized it moves the control lever 41 from the position E into position F with the same effect as described in the previous example.

For the selective operation of solenoid 55 a keyboard T1, T2, T3 etc. is provided on the outside of the apparatus for cooperation with a rotary switch. The rotary switch includes a set of contacts K1, K2, K3, etc. arranged along a circle on a stationary support 54 in the frame. A rotating arm 53 is mounted on a secondary shaft 52 and carries a contact 53a which during rotation of arm 53 travels on a circle of the same diameter of, and con centric with, the circle on which the contacts K1 etc. are located spaced from each other and associated respectively with the sections Z1, Z2, Z3, etc. of the printing form 2. The shaft 52 is in driving connection with the printing roll 1 by means of a gear train 49, 5t), 51. Since the gears 49 and 51 are of the same diameter the arm 53 will rotate with its shaft 52 in synchronism with :the printing roll 1. The arm 53 is provided with a contact ring 53b which in turn is connected with the sliding contact 53a and a contact spring 53c bears continuously on the contact ring 5312. In operation the'contact 53a successively engages the stationary contacts K1, K2, K3, tetc. thereby closing a circuit which includes the solenoid 55 and associated selector switches operated by and connected with the keys T1,'T2, T3, etc. of the keyboard. It is evident that a circuit will be closed by the cooperating contacts of the rotary switch only if the key corresponding to a particular stationary contact of the set K1 etc. has been previously moved into closed position. Whenever'a selected circuit is closed in this manner the solenoid 55 is energized and through operation of the control valve 19 and to the hydraulic device the counter roll 12 is then momentarily moved into printing position was to cause the reproduction of the selected section of the printing form. In order to accelerate the energization and reaction of the solenoid 55 means are provided in order to operate the solenoid on direct current if so desired. For this purpose a rectifier and a circuit containing in parallel a condenser and a resistor are both connected in series with the solenoid 55 between the latter and the source of alternating current U.

It can be seen from the above, that in the embodiment illustrated by Figs. 1 and 2 the actuating members are pins S1, etc. shiftable transversely into' and from operative position, and that the cooperating second actuating means is the rocker arm 36 which is connected to the control valve 19 by shifting means comprising the link 40 and lever 41. In this embodiment the operating members of the selector device are the handles or buttons connected with the pins S1 etc. and permitting to move the latter into and from their operative position.

On the other hand, in the embodiment shown in Figs. 3, 4 the solenoid 5S and its armature constitute the shifting means which are connected by link 56 and lever 41 to the control valve 19, while the operatingmembers of the selector device are the key-operated switches T etc., and the actuating members are the fixed contacts K etc. which cooperate with the sliding contact 53a on the rotary arm 53.

It will be understood that each of the elements described above, or two or more together,'may also find a useful application in other types of printing apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in printing apparatus for selected intermittent printing, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a printing apparatus for selective intermittent printing, in combination, a frame; a rotary printing roll mounted on said frame and adapted to have printing form attached thereto; a counter roll supported on said frame for movement to and from a printing position in close proximity to said printing roll for pressing a copy sheet passing between said rolls against said printing form; a hydraulic operating device including a movable'member operatively connected to said counter roll for moving the same to and from said printing position, said hydraulic operating device including valve means movable between two positions for advancing and retracting said movable member, respectively; a shifting means for shifting said valve means between said positions thereof; a set of control means respectively associated with sections of said printing form, each control means having an operative and an inoperative condition; means for successively connecting control means in operative condition to said shifting means during rotation of said printing roll, said shifting means being actuated whenever one of said control means in operative condition is connected to said shifting means; and selector means including a set of operating members respectively associated with sections of said printing form and with said control means, said operating members being selectively movable to and from an operative position for placing the associated control means in said operative condition.

2. In a printing apparatus for selective intermittent printing, in combination, a frame; a rotary printing roll mounted on said frame and adaptedto have a printing form attached thereto; a counter roll supported on said frame for movement to and from a printing position in close proximity to said printing roll for pressing a copy sheet passing between said rolls against said printing form; hydraulic operating device including a movable member operatively connected to said counter roll for moving the same to and from said'printing position, said hydraulic operating device including a control valve means movable between operative and inoperative positions for advancing and retracting said movable member, respectively; a shifting means for shifting said control valve means between said positions thereof; a rotary supporting element connected to said printing roll for rotation therewith; a stationary supporting element supported on said frame; an actuator device having first actuating means including a plurality of actuating members respectively having an operative condition and an inoperative condition, and second actuating means, said actuating members being mounted on one of said supporting elements spaced along a circular path having its center in the axis of rotation of said rotary supporting element, and said second actuating means being located along said circular path and mounted on the other supporting element so that said actuating members successively cooperate with said second actuating means, said second actuating means being connected to said shifting means for actuating the same whenever said second actuating means cooperate with an actuating member which is in said operative condition; and a selector device including a set of operating members respectively associated with sections of said printing form and being selectively movable to and from an operative position in which the associated actuating member is placed in operative condition so that during rotation of said printing roll and of said rotary supporting element said shiftingmeans actuates said control valve means for moving said counter roll to said printing position whenever said second actuating means cooperates with an actuating member in said operative condition.

3. A printing apparatus as set forth in claim 2 wherein said shifting means is an electromagnetic means having a shiftable member-connected to said control valve means; wherein said operating members of said selector device each include a contact means; and wherein said actuating members are first contacts; wherein 'said second actuating means is a second contact, said second contact successively engaging said first contacts; and including circuit means connecting said contact means with said first and second contacts and with said electromagnetic means.

4. A printing apparatus as set forth in claim -2 wherein said actuating'members are pins mounted on said rotary supporting element for movement to and from an operative position; wherein said second actuating means is a rocker arm pivotally mounted on said stationary supporting element and having a portion projecting into the circular path of said actuating pins in operative position so that said rocker arm is operated whenever said portion engages one of said actuating pins in operative position; wherein said shifting means is a linkage connecting said rocker arm with said control valve means; and wherein said operating members of said selector device are respectively connected to said actuating members for shifting said actuating members to and from said operative position.

.5. In a printing apparatus for selective intermittent printing, in combination, a frame; a rotary printing roll mounted on said frame and adapted to have a printing form attached thereto; a counter roll supported on said nected to said movable member and movable in said cylinder, duct meansfor an operative fluid leading to said cylinder and a valve cone'cted with said duct means and movable between two'positions for controlling the flow of said fluid to said cylinder, said valve in one position causing said piston to advance said movable member and in the other position causing said piston to retract said movable member; shifting means for shifting said control valve between said two positions thereof; a set of control means respectively associated with sections of said printing form, each control means having an operative and an inoperative condition; means for successively connecting control means in operative condition to said shifting 'means during rotation of said printing roll, said shifting means being actuated whenever one of said control means in operative condition is connected to said shifting means; and selector means including a set of operating members respectively associated with sections of said printing form and with said control means, said operating members being selectively movable to and from an operative position for placing the associated control means in said operative condition.

6. An arrangement as set forth in claim wherein said hydraulic operating device includes an adjustable relief valve, said relief valve being connected to said duct means for permitting excessive amounts of said fluid to return to said hydraulic device when said piston reaches the end of its stroke, and adjusting means for controlling said relief valve for predetermining the maximum pressure acting on said piston whereby the pressure exerted by said counter roll on said copy sheet can be predetermined by corresponding adjustment of said adjusting means.

7. In a printing apparatus for selective intermittent printing, in combination, a frame; a rotary printing roll mounted on said frame and adapted to have a printing form attached thereto; a counter roll supported on said frame for movement to and from a printing position in close proximity to said printing roll for pressing a copy sheet passing between said rolls against said printing form; hydraulic operating device including a movable member operatively connected to said counter roll for moving the same to and from said printing position, said hydraulic operating device including a control valve means movable between operative and inoperative positions for advancing and retracting said movable member, respectively; a set of fixed contacts mounted on said frame, a rotary arm mounted on said frame connected with said printing roll for rotation therewith and including a contact member, said set of contacts being respectively associated with consecutive sections of said printing form and being located spaced from each other along a circle having its center in the axis of rotation of said rotary aim, said contact member being spaced from said axis a distance equal to the radius of said circle, so that said contact member during rotation successively cooperates with said contacts; electromagnetic shifting means mounted in said frame for operating said control valve means, and ineluding a'movable member connected to said control valve for moving the same into operative position when said electromagnetic means is energized; a set of operating switches mounted on said frame and respectively asso-- ciated with said contacts and with sections of said printing form, said switches being selectively movable from a cir-- wit-interrupting position to a circuit-closing position in which the associated contact in said set of contacts is placed in operative condition; and circuit means respectively connecting said contacts with said operating switches and with said electromagnetic means, whereby said control valve is moved into operative position and said counter roll is advanced into, said printing position whenever during rotation said contact member meets selected contacts placed in operative condition by the associated operating-switches in circuit-closing position.

8. In a printing apparatus for selective intermittent printing, in combination, a frame; a rotary printing roll mounted on said frame and adapted to have a printing advancing and retracting said movable member, respec tively; a rotary support mounted in said frame for rotation with said printing drum; a set of pins respectively associated with sections of said printing form and mounted on said rotary support, said pins being movable to and from an operative position 'in which operative portions thereof are located along a circle having its center in the axis of rotation of said rotary support; means at tached to each of said pins for selectively moving the same to and from an operative position thereof; a rocker arm turnably mounted in said frame and having a por- 'tion' projecting into the circular path of said operative portions of said pins in operative position for engagement therewith; and a linkage connecting said rocker arm with said control valve so that said valve is moved into its operative position whenever one of said pins in operative position engages during rotation of said rotary support said portion of said rocker arm.

9. An arrangement as set forth in claim 8, including control means for moving said rocker arm into a position in which said portion thereof is retracted from said circular path, said control means including cam means mounted in said frame for turning to and from an operative position in which said cam means engages said rocker arm and moves it with its said portion into inoperative position and advances said control valve into operative position, whereby during rotation of said printing roll and said rotary support all sections of said printing form are printed in consecutive order.

References Cited in the file of this patent UNITED STATES PATENTS 615,107 Schwarzschild Nov. 29, 1898 2,205,720 Goebel June 25, 1940 2,210,021 Breitling Aug. 6, 1940 2,267,380 Tyler Dec. 23, 1941 2,569,034 Auer Sept. 25, 1951 2,753,791 Thurmann July 10, 1956 2,758,539 Ritzerfeld Aug. 14, 1956 

